5th International Conference on Advances in Solidification Processes (ICASP-5) 5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining (CSSCR-5)

Thermal-solutal convection necessary occurs during the terrestrial solidification of alloys. Thanks to the recent progress in the in-situ observation technique using X-ray radiography, the direct observation of dendrite growth under high temperature has been made possible. In the in-situ observation, however, it is difficult to see the liquid flow during the dendrite solidification. In order to clarify the physics occurred in the images obtained in the in-situ observation, it is essential to reproduce the same phenomenon by the numerical simulation. Although a phase-field method is the most powerful numerical tool to simulate the dendrite growth, the high computational cost is a drawback. Moreover, the computational cost of the phase-field simulation coupled with thermal diffusion, solute diffusion, and melt convection is quite expensive. Therefore, the most phase-field simulations of dendrite growth performed so far are limited to a single dendrite growth or dendrites growth in two-dimension. In this study, we develop a high performance computing scheme of the three-dimensional phase-field simulation for the dendrites growth with thermo-solutal convection. The computations are accelerated by a multi-GPU parallel computation in a GPU supercomputer, TSUBAME3.0 at Tokyo Institute of Technology. Then, we introduce the large-scale phase-field simulations of dendrite growth taking into account the thermal-solutal convection.